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Richard read, his eyes moving on the pages.
“The first method for purifying uranium 235 is the electromagnetic separation method, which uses the principle of a mass spectrometer to separate isotopes.
The mass spectrometer is an instrument used in laboratories to analyze the mass of charged particles. It allows particles with different masses but the same charge to enter a magnetic field and deflect at different radii, thereby separating them.
To explain in detail, the particle enters the magnetic field at a speed v (assuming it is pointing upward). The magnetic field lines generated by the movement of positively charged particles point upward along the left side of the direction of movement and downward on the right side. Therefore, the magnetic field on the left side of the moving charged particle is strengthened, and the magnetic field on the right side is weakened, forming a magnetic field gradient and generating a magnetic pressure pushing from left to right.
This force is perpendicular to the direction of velocity. Although it cannot change the velocity value of moving charged particles, it can change the direction of particle motion and form a centripetal force.
And because the magnetic field is uniform, the magnetic pressure produced on the moving charged particles is equal everywhere, so the moving charged particles make uniform circular motion in the magnetic field.
According to the electromagnetic formula, it can be seen that the force of the magnetic field is equal to qBv, and the centripetal acceleration is equal to v2/R.
Therefore, it can be derived: qBv=Mv2/R→qBR=Mv.
In the formula, q is the charge of the particle, v is the velocity of the particle, M is the mass of the particle, B is the magnetic induction intensity, and R is the deflection radius of the particle in circular motion.
And because the particle electric charge q and the magnetic induction intensity B are both determined, the momentum of the moving particle is proportional to the deflection radius.
Ions with the same charge q but different masses obtain the same electric potential energy through the same acceleration voltage U, and are equal to the kinetic energy when entering the magnetic field: qU=(1/2)Mv2.
It is known before that the momentum of the particle Mv=qBR, and v is eliminated from the two equations, we get M=qB2R2/2U.
For particles with mass equal to (M+DM), (M+DM)=qB2(R+DR)2/2U.
It can be concluded that DM/M=2DR/R, that is, the relative deviation of mass is twice the relative deviation of radius.
Since the masses of the incident particles are different, they gain equal energy but different momentum after being accelerated by the same voltage. After entering the magnetic field, the bending radius with large momentum is large, and the bending radius with small momentum is small.
If the angle at which ions with the same momentum enter the magnetic field is skewed, they will focus together in the range of D. Then the relationship between the range of D and the incident angle can be calculated as follows: DR/R≈0.5q2.
When q is less than 50, the relative error of R is 4/1000, and the possible quality deviation is 8/1000. The relative mass difference between uranium 235 and uranium 238 is equal to 13/1000, which makes the mass spectrometry separation method practical... "
After Richard finished reading, he raised his eyebrows.
This is obviously a very simple and easy-to-understand method. The principle is: particles with different masses but the same charge have different momentum after being accelerated by the same voltage, which results in different radii of deflection when entering the magnetic field.
For example, this is like a train running on a track. At a curve, a train with a suitable speed can pass normally. A train that is traveling too fast will, due to unbalanced forces, take the carriages directly off the track, causing a derailment.
Using this method, uranium-235 is the train at the right speed, and uranium-238 is the train at too fast speed, allowing the two to be separated to obtain high-purity uranium-235.
The technical content of this method is relatively low, so on earth, in 1938, German chemists Hahn and Strassmann discovered nuclear fission, and Meitner and Frisch proposed a theoretical explanation of nuclear fission. Just two years later, in April 1940, Neal at the University of Minnesota used a mass spectrometer to produce trace amounts of enriched uranium-235.
Then in 1942, the Manhattan Project to create nuclear weapons for the first time on earth began. Lawrence and others began to use electromagnetic isotope separators to purify uranium 235.
This is a proven method and is completely feasible.
However, it also has a slight problem.
That's too much investment.
In the Manhattan Project on Earth, in order to purify uranium-235 in this way, a super electromagnetic device was built in Oak Ridge. Nearly 25,000 people were invested, more than 1,100 separators were used, and 15,000 tons of silver was used to wind the coils alone.
15,000 tons!
The result was only a few grams of uranium-235 produced every day. After several years, the amount of uranium-235 obtained was just enough to make an atomic bomb.
Richard pursed his lips.
He doesn't have tens of thousands of men now, nor does he have fifteen thousand tons of silver. If he really wants to use this method to produce, he has to solve the prerequisites first.
If this is the only way, he may really have to consider creating a private force in advance, but fortunately, this is not the only way, and he has other options.
Read on.
“The second method for purifying uranium 235 is the gas diffusion method.
As the name suggests, the principle used in this method is common gas diffusion.
For example, if you sprinkle a drop of perfume in a corner of the bedroom, the perfume molecules will spread quickly, and soon the entire room will smell the perfume.
If you replace a drop of perfume with a drop of vinegar and sprinkle it in the same corner of the bedroom under the same conditions, it will take longer to smell the vinegar throughout the room.
This is because vinegar molecules are heavier than perfume molecules and therefore diffuse more slowly.
Correspondingly, a balloon is filled with hydrogen (relative molecular mass is 2) and nitrogen (relative molecular mass is 28, which is 14 times that of hydrogen). When a balloon deflates, hydrogen gas leaks faster than nitrogen gas because hydrogen molecules are smaller and lighter.
By applying the gas diffusion method to uranium, the two isotopes uranium-235 and uranium-235 can be separated based on the same distance.
The specific operation can be carried out as follows: place uranium hexafluoride in an environment above 64.8°C (338.0K), and the uranium hexafluoride will sublimate into gas. Then, the gaseous uranium hexafluoride is forced towards the porous membrane. According to the principle of gas diffusion, the uranium hexafluoride gas molecules containing uranium 235 will pass through the membrane faster than the uranium hexafluoride gas molecules containing uranium 238. Its diffusion rate will be inversely proportional to the square root of its gas molecular weight.
In this way, by setting the pore size of the porous membrane to be as small as the average distance traveled by a gas molecule between two collisions with other gas molecules, optimal conditions for gas diffusion are obtained. This allows light molecules to move faster than heavy molecules and pass through the membrane pores more easily.
Through data collection, it can be determined that the pore size of the porous membrane is controlled below 0.02 microns and the uranium hexafluoride is maintained at 85°C while gas feeding is continuous. The gas that diffuses through the membrane (enriched flow) will be approximately 0.2% more enriched than the uranium-235 in the feed gas (feed)..."
After reading the second method, Richard thought.
The principle of this second method is also very simple and easy to understand, it is just the difference in the movement rate of molecules involved in gas diffusion. As long as we can grasp this point, we can continue to increase the content of uranium 235.
The only problem is that according to data, the concentration of uranium-235 increases by only about 0.2% each time it passes through the porous membrane.
In this way, in order to increase the content of uranium-235 to a certain level, to a level that can actually produce nuclear weapons, many separation stages need to be connected in series.
Moreover, a single or two-level series connection will not have much effect. Thousands of levels of series connection are needed.
In fact, this method was adopted during the Manhattan Project on Earth. To this end, a huge factory was built in Oak Ridge and thousands of levels of separation equipment were assembled.
In this way, the scale is obviously huge, comparable to the scale of the first method. In addition, in order to ensure that the diffusion gas continues to spread in the same direction, a strong power is needed.
For this reason, the entire country's power supply must be tilted towards gas diffusion plants.
It can be said that whether it is the first method or the second method, if it is really put into practical operation, it requires the support of most of the national power of an extraordinary modern country.
For this reason, countries that can develop and produce nuclear weapons on their own can be regarded as representatives of the most powerful power on earth and a symbol of absolute strength. It is for this reason that such a country is respected and cannot be ignored.
But these are a bit difficult for Richard to do now.
He pursed his lips and continued to look down.
"The third method for purifying uranium 235 is centrifugal separation..."
"The fourth method for purifying uranium 235 is the nozzle separation method..."
"The fifth method of purifying uranium 235 is..."
“Uranium 235…”
After quickly browsing most of the content, Richard shook his head.
There are indeed many methods for purifying uranium 235, and most of them are based on the subtle mass difference between uranium 235 and uranium 238. Compared with the first and second methods, these methods are similar and require high manpower and material resources.
To use this method, he needs to first create a huge private power.
But in his mind, it is not time to create a private power now.
Frowning slightly, Richard patiently continued reading, and finally stopped at a page of the book.
“The ninth method for purifying uranium-235 is laser separation.
This is a relatively advanced method. The starting point of its principle is that because isotopes have different masses, their energy levels are also different, resulting in certain differences in the absorption spectra when excited from low energy levels to high energy levels.
In this way, by selecting lasers of different wavelengths to excite only one of the isotopes, the differences in physical and chemical properties between the excited isotope and the non-excited isotope can be used to separate them using appropriate methods.
Uranium-235 and uranium-238 atoms and their compound molecules have been determined through experiments to comply with this method. In the experiment, a laser was used to excite uranium hexafluoride gas molecules containing uranium 235, which can change the uranium 235-containing molecules without affecting the uranium hexafluoride molecules containing uranium 238. A second laser is then used to split the excited molecules into uranium pentafluoride, which is then recycled as a white powder...
In fact, uranium metal can also be directly manipulated using the atomic vapor laser isotope separation process. Specifically, a focused electron beam is used to locally heat a uranium metal ingot to 3000°C in a vacuum environment, causing the uranium metal to vaporize into the atomic states of uranium 238 and uranium 235.
A laser was then used to ionize the uranium 235 atoms in the uranium vapor, while the uranium 238 atoms were not affected. After removing electrons, collecting uranium 235 using electromagnetic methods can greatly improve the purity... "
After reading this method, Richard's eyes lit up slightly.
He could see that the laser separation method had outstanding advantages compared with previous methods.
First of all, the first point is that the separation coefficient is large and the method is simple.
The second point is that it consumes less power. According to some calculations from some data in the method, the power required by the laser separation method may be less than one-tenth of that of the diffusion method.
You must know that on Earth, the Manhattan Project consumed almost 1,700 megawatts of electricity in order to use the gas diffusion method, which was too difficult. If it is reduced to one-tenth, it can still be barely considered.
The third point is that the size of the device is relatively small, and it does not require much manpower and material resources. At the time, the Manhattan Project used the gas diffusion method, with thousands of separation stages, and the factory covered an area of 240,000 square meters. The laser separation method only requires a simple level, and the area required for the equipment is also greatly reduced.
Generally speaking, laser separation method is the best choice at present.
However, Richard did not draw premature conclusions. He read on again and read the entire book before nodding and saying to himself: "The laser separation method is easier to implement. In this case... just give it a try."
After saying that, Richard stood up with the book and walked out of the room.
The stone turtle statue that Richard was sitting on came back to life. Crawling, following Richard, he passed through several oak doors, returned to the original place, and stood still little by little.
Richard was about to walk out of the library door with his books in hand. He turned his head and looked at the turtle statue. When he saw the turtle statue, he also looked over.
Richard blinked and said, "Suma, the problem I encountered has been solved, and now I'm leaving."
"I'm glad to hear you say that, my creator." The turtle statue spat, its head moving slightly, "At the same time, I look forward to seeing you next time."
"I will." Richard smiled and walked out of the library with the books.
In the library, the turtle stone statue's slightly moving head stopped, its whole body froze, and returned to its original motionless state, turning into a real stone statue.
Outside the library, Richard walked on the path paved with bluestones, admiring the scenery. After walking for a while, he lightly touched the ground, and his whole body flew up at high speed, straight into the sky.
Soon, Richard rushed out of the atmosphere, left the planet, and came to the empty outer space.
Looking around, Richard looked at the stars one by one like a military parade and made some adjustments.
If you see that the stars in some places are too dense, wave your hand to control the scattering of the stars. If you see that the stars in some places are too sparse, wave your hand to make the stars in other places move over.
Later, Richard saw a star nearby that was dim and red, and was expanding in size, preparing to swallow several planets surrounding it. This indicates that the star is about to end its lifespan and has left the ranks of main sequence stars and transformed into a red giant.
Looking over, Richard soon learned about the galaxy of this star, which recorded some time-sensitive information. For him, it is completely meaningless, and it is an existence that needs to be cleared to make room for other knowledge.
Without hesitation, Richard crumbled the entire galaxy into a ball with a wave of his hand, and then threw it towards the black hole in the distance - which was equivalent to the recycling bin in the memory palace.
Watching the galaxy being swallowed by the black hole and emitting intense radiation, Richard turned his head and began to adjust to other places.
Finally confirming that there is no big problem in the entire memory universe and that it can keep moving for a long time, Richard nodded with satisfaction and left here with the book in his hand.
"Collapse!"
Richard spoke out, and the entire universe suddenly shrank toward him, squeezed into a singularity, and then exploded, releasing a dazzling light.
That light is the illumination of reality.
In the real world, on the small bed in the main laboratory of Eden, Richard slowly opened his eyes.
There was nothing in his hands at this time, and he did not bring out any books, but the relevant knowledge had been transferred to the shallow memory of his brain.
"Laser separation method, let's start."
Richard said, blinking, stood up and walked out.
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